Method and system for hybrid coherent and incoherent diffractive beam combining

A system for combining light beams of different and identical wavelengths into a single composite beam of substantially identical shape as the individual beams, comprising:

• N oscillators, each transmitting a light beam at a different one of N wavelengths;
• one or more beam splitters for splitting each one of the N beams into M beams of common wavelength;
• a phase modulation stage for locking phases of the M beams at each N wavelength according to phase correction signals;
• an optical element having both an SBC grating and a diffractive element, whereon incident M×N light beams are combined into a single composite beam comprising N incoherent beams spectrally combined by the grating, each incoherent beam a combination of M beams combined by the diffraction grating at one of the N wavelengths;
• a phase detection means for detecting the phases of the M beams at each N wavelength;
• and
• a means for deriving the phase correction signals from the detected phases;
• wherein M and N are integers.

A method for combining light beams of different and identical wavelengths into a single composite beam of substantially identical shape as the individual beams, comprising:

• transmitting light beams at N different wavelengths;
• splitting each one of the N beams into M beams of common wavelength;
• synchronizing phases of the M beams at each N wavelength according to phase correction signals;
• combining M×N light beams into N incoherent beams, each incoherent beam a coherent combination of M beams at one of the N wavelengths;
• extracting a sample beam from each of the combined incoherent beams;
• detecting in the sample beam the phases of the M beams at each of N wavelengths;
• deriving the phase correction signals from the detected phases;
• and
• spectrally combining the N incoherent beams into a single composite beam;
• wherein M and N are integers.